Illuminated push button



1967 w. A. DE SMIDT ET AL 3,335,249

ILLUMINATED PUSH BUTTON 2 Sheets-Sheet L Filed Sept. 16, 1966 Q I I VINVENTORS WOODROW A. DE SMIDT ALBERT d. ZIEBELL g- 3, 1967 w. A. DESMIDT ET AL 3,335,249

ILLUMINATED PUSH BUTTON Filed Sept. 16, 1966 2 Sheets-Sheet INVENTORSWOODROW A. DE SMIDT ALBERT J. ZIEBELL United States Patent 3,335,249ILLUMINATED PUSH BUTTON Woodrow A. De Smidt, Whitefish Bay, and AlbertJ.

Ziebell, Oshkosh, Wis, assignors to Allen-Bradley Company, Milwaukee,Wis., a corporation of Wisconsin Filed Sept. 16, 1966, Ser. No. 580,04710 Claims. (Cl. Nil-167) This invention pertains to an illuminated pushbutton and more particularly to the use of an illuminated push buttonincorporating a transformer to supply the proper voltage to theilluminating lamp used in the push button.

The combination of a :push button and an integral illuminating source toindicate desired conditions of the circuit to be controlled have becomecommercially significant. The illuminating lamp to be used in such aunit usually has a maximum voltage reading which is substantially lessthan the voltage which is to be controlled through the switch integralto the push button.

However, it is advantageous to utilize the relatively high voltageconnected to the push button switch as the voltage source for theilluminating bulb. One solution has been the use of a resistance elementbetween the lower voltage load involved and the source voltage. Bycontrast, the push button of this invention utilizes what has become amore effective and efiicient approach, viz. the use of a transformerbetween the lower voltage illuminating bulb and the voltage controlledby the push button switch or like voltage source.

It is an object, then, of this invention to provide a compactilluminated push button incorporating a transformer; which push buttonis housed as a unit of minimum size requiring minimum installationspace.

A further object of this invention is to provide an illuminated pushbutton utilizing a construction which is extremely simple and thereforeefiicient and effective.

A still further object of this invention is to provide an illuminatedpush button with a transformer, which transformer is movable so as tophysically transfer the external initiating force from the point ofapplication to the switch of the push button.

These and other objects of the invention will become apparent from thefollowing description and the accom- .panying drawings. It is to benoted, however, that the following description and the accompanyingdrawings are directed to an exemplary embodiment of the invention, only,and that the scope of the invention is to be found in the appendedclaims.

In the drawings:

FIGURE 1 is an isometric view of the push button constituting thisinvention.

FIGURE 2 is a partial cross-section of a side view taken along lines 2-2of FIGURE 1 showing the push button in a position resulting from anexternal force being applied thereto.

FIGURE .3 is a partial cross-section of a side View taken along lines 33of FIGURE 1 and similar to FIG- URE 2 but showing the push button in anormal position without an applied external force.

FIGURE 4 is a break away view showing switch detail of the push button.

FIGURE 5 is a cross-sectional plan view taken along line 5-5 of FIGURE3.

The illuminated push but-ton is shown as a unit in FIG- URE 1 andcomprises basically the housing 1, actuator portion 2 and the terminalassembly 3. By applying an external force to the actuator portion 2, aswitch located internally of the housing 1 is controlled. In order totransfer this motion from the actuator 2, this invention incorporates aconstruction which is simple and therefore inexpensive,.while at thesame time providing a very compact unit of minimal size.

This construction utilizes the transformer 5 to transfer the mechanicalmotion. As can be seen from FIGURES 2, 3 and 4, this transformer 5 islocated in the housing 1 and is movable therein. Guide means shown inFIG- URES 4 and 5 as internally molded strips 6 mate with the grooves 7of the transformer 5 to supply the necessary guidance.

The actuator portion end 2 is best shown in the partial cross-sectionsof FIGURES 2 and 3. Here, the end of the housing 1 has a bushing 10which terminates in the cylindrical portion 11 with threads of theexterior thereof. The mounting ring 9 screws on the threads ofcylindrical portion 10a so that any surface upon which the push buttonis to be mounted can be secured between the mounting ring 9 and thehousing 1 at upper, external portion of bushing It The inner cylindricalsurface of the cylindrical portion 10:: guides a cylindrical plunger 11which is independent of the transformer 5 at one end but connected tothe lens 12 by the internally threaded lens mounting ring 13. Thus, anexternal force applied to the lens 12 is transferred through the motionof the lens mounting ring 13 and the plunger 11 to the transformer 5.This contact between the plunger 11 and the transformer 5 is establishedthrough the flange 14 of the plunger 11.

Integral to the transformer 5 is the necessary connections for theilluminating lamp 20. In particular, one connector from a first terminal26 of the transformer 5 is shown in FIGURES 2 and 3 as connector 21which leads from the terminal 26 to the base 22 for the illuminatinglamp 20. A similar conductor is shown in part as 23 in FIGURES 2 and 3;and as with the conductor 21, this conductor 23 is connected to thesecond terminal (not shown) of the transformer 5. As will be understood,the transformerin conventional fashion-has a primary and secondarywinding which are not shown in the drawings. The conductors 21 and 23are connected at terminals such as terminal 26 to the secondary windingof the transformer 5 so as to provide the reduced voltage necessary forthe illuminating lamp 20. In between the conductors 21 and 23, is aninsulating disc 24. An O-ring 25 is located between the plunger 11 andthe bushing 10 so as to provide a seal therebetween.

The plunger 11 essentially provides the stop structure necessary forlimiting push button motion in either direction. When moving in aninward or a downward direction as viewed in FIGURES 2 and 3, the lensmounting ring 13 which is essentially integral to the plunger 11 abutsthe uppermost portion of the housing 1 at surface 27 which is a part ofthe cylindrical portion 10a of bushing 10. The movement of the plunger11 in the opposite direction is limited when the flange 14 abuts theinner wall of the housing 1 at surface 28 or the lower surface of thebushing 10. Thus, it will be seen that outward or upward motion of theplunger 11 is limited in FIGURE 3 as the flange 14 of plunger 11 meetsthe surface 28 of the housing 1 while the downward motion of the plunger11 is shown in FIGURE 2 to be limited as the plunger 11 through lensmounting ring 13 abuts the surface 27 of the housing 1.

The particular function or functions of the switch means integral to thepush button and the accompanying on or off condition of the illuminatingbulb 20 are variables. For example, the switch may not be directlyconnected to the transformer circuit; but rather the switch can beconnected through terminals of the push button to; an external unit suchas a motor while the transformer circuit can be independentlythroughterminals of the push button distinct from the switch connectedterminalsconnected to sensing units of external unit. Thus, thetransformer motion operates the switch of the push button but the lampillumination is not directly dependent upon the transformer motion.Moreover, the switch of the push button can be of several types such asa single pole or double pole switch which again may or may not bedirectly responsive to movement of the transformer. An example of anilluminated push button of this invention which causes the illuminatingbulb to respond directly with the movement of the transformer is seenwhen the switch is electrically connected between the transformer andthe push button terminal so that'the switch position determines whetherthe bulb will be on or ofi'.

The particular embodiment shown in the drawings illustrates a highlysuccessful switch means electrically conencted between the transformerprimary and the push button terminal and used to handle the control oftwo separate circuits. This function has particular value when it isdesirable to periodically and temporarily test one circuit and thenreturn to reclose the normally closed circuit.

The switching structure is shown in its functional condition by FIGURES2, 3 and 5, while FIGURE 4- shows more details through an explodeddiagram. Circuit closing contact is made through a pivoted contact blade32 which is shown in FIGURE 4 and has two U-shaped portions 33 uponwhich the pivoting motion is accomplished. These U-portions 33 pivot inthe grooves 34 of the terminal assembly 3. Also, fastened to theterminal assembly 3, but in the grooves 36 and 37, are fixed contacts 38and 39. As will be seen, these fixed contacts 38 and 39 take the form ofU-shaped spring members and are connected to a respective terminal 40(e.g. 40a, 40b or 406) by the rivets 42.

The transformer has the two terminals 45 and 46 connected to the primarywindings. Terminal 45 hasCOnnected thereto a conductor 47 which reachesto the center of the transformer 5 and forms a ring. A molded locaterpin 48, integral to the transformer 5, helps establish the location forthe conductor 47 during manufacturing. Electrical connection between theterminal40b and the transformer terminal 45 is accomplished through thespring 50 which serves the dual purpose as a conductor and as a biasingmeans to bias the transformer 5 in an upward direction as shown in theFIGURES 2, 3 and 4. Electrical connection between the spring 50 and theterminal 40b is established through a rivet 51 in the terminal assembly3. A molded ring 52 in the terminal assembly 3 helps locate the spring50 during assemblyand isolate it electrically from the remainingportions of theswitch.

The terminal 46 of the transformer 5 is connected to the contact blade32 by way of spring 55 which also serves a dual purpose, viz. anelectrical conductor and a biasing means which encourages the adjacentend of the contact blade 32 towards the fixed contact 38 as will befurther explained below. A molded electrical barrier 56 is a part of thetransformer 5. The screw 58 in FIG- URE 4 illustrates the means by whichterminal assembly 3 is attached to the housing 1 by means of the holes59 located in the internally molded strips 6 of the housing 1. Push pin60 is integral to the transformer 5 so as to abut the contact plate 32on the side of the pivot point formed by the U-shaped portions 33 butopposite from the biasing spring 55.

In operation, the push button is moved from the position of FIGURE 3 tothe position of FIGURE 2 through an external operating force. Forexample purposes, the terminals 40 will be connected to two externalcircuits with terminal 40b acting as acommon for these two circuits. Thecurrent for the first circuit will travel through terminal 40b and therivet 51 to the spring 50, the conductor 47 and to one side of theprimary of transformer 5 by way of the terminal 45. The other side ofthe pri-- mary of the transformer 5 is connected to the terminal 46 andthen through the spring 45 to the contact blade 32. Here,.the contactblade 32 can be pivoted upon pivot point 33 to complete a circuit toeither that circuit wired to terminal 40a or terminal 40c.

the lens 12 is transferred through the lens mountingring 13 to theplunger 11 and then to the transformer 5 as the flange 14 contacts thelatter. With sufficient ex ternal force, the bias of spring 50 isovercome and the transformer 5, guided by the internally molded strips6, moves in a downward or inward direction and the push .pin 60,abutting the contact blade 32 pivots this contact blade 32 so that thecircuit including fixed contact 39 is closed and the circuit includingfixed contact 38 is open.

As the push pin 60 pivots the contact blade 32, the smaller spring 55 iscompressed so that when the condition of FIGURE 2 is reached, both thesprings 50 and 55 are in'a compressed condition. Upon removal of theexternally applied force of the lens 12, these springs 50 and 55 returnthe unit to the condition of FIGURE 3. That is, the spring 50 moves thetransformer 5, plunger 11 and lens 12 upwardly or outwardly and thespring 55 pivots the contact blade 32 so as to open the circuit withfixed contact 39 and close the circuit with fixed contact 38.

We claim:

1. An illuminated push button comprising:

(a) a housing,

(b) a transformer movably located in said housing having two sets ofterminals,

(c) a lamp bulb connected to a first of said terminal sets,

(d) guide means in said housing to guide said transformer movement,

(e) a lens at least partially enclosing said lamp bulb and mechanicallyconnected to said transformer for movement therewith,

(f) switch means actuated by movement of said transformer,

(g) said second set of transformer terminals electrically connected toterminal means.

2. The illuminated push button of claim 1 wherein said electricalconnection between said second set of transformer terminals and saidterminal means includes said switch means.

3. The illuminated push button of claim 2 wherein:

(a) said switch means has atleast two separate sets of contacts whichrespond independently to movement of said transformer,

(b) at least part of said terminal means connected to said sets ofcontacts so as to permit connection of separate circuits by said pushbutton.

4. The illuminated push button of claim 3 wherein:

(a) said sets-of contacts comprise,

(l) a pivoted contact blade,-

(2) fixed contacts connected to first and second of said terminal meansand located at either side of a pivot point of said contact blade,

(b) a thirdof said terminal means electrically connected to a first ofsaid second set of transformer terminals (0) means electricallyconnecting a second of said second set of transformer terminals withsaid contact blade to permit completion of an electrical circuit througha respective fixed contact.

5. The illuminated push button of claim 4 wherein a spring means biasessaid movable transformer and provides at least in part said electricalvconnection to said first of said second setof transformer terminals.

6. The illuminated push button of claim 1 wherein:

(a) said housing includes a sleeve,

(b) plunger means are guided by said sleeve and me,- chanicallyinterconnect said lens and said transformer to transfer motiontherebetween,

(0) spring means bias said movable transformer.

7. The illuminated push button of claim 6 wherein said plunger abutssaid housing to stop motion of said transformer.

8. The illuminated push button of claim 1 wherein said lamp bulb is anintegral part of said transformer.

9. An illuminated push button comprising:

(a) a housing,

(b) a transformer movably located in said housing with a lamp bulbintegral thereto at one end and electrically connected to a secondarywinding therein,

(c) guide means in said housing to guide said transformer movement,

(d) a lens at least partially enclosing said lamp bulb,

(e) a sleeve in said housing concentric to said lamp bulb,

(f) a movable plunger guided by said sleeve and abutting said lens andtransformer so as to transfer motion therebetween,

(8) switch means located at an end of said housing opposite from thesleeve and abutting said movable transformer for movement therewith,

(h) terminal means adjacent said housing at said switch means end andelectrically connected to a primary Winding of said transformer.

10. The illuminated push button of claim 9 wherein:

(a) said electrical connection between said primary winding of saidtransformer and said terminal means includes said switch means,

(b) said switch is located in said housing.

References Cited UNITED STATES PATENTS 2,979,593 4/1961 White 200-1673,231,706 1/1966 Waldorf 200167 3,244,935 4/ 1966 Robbins et a1. 20067ROBERT K. SCHAEFER, Primary Examiner.

20 H. O. JONES, Assistant Examiner.

1. AN ILLUMINATED PUSH BOTTON COMPRISING: (A) A HOUSING, (B) ATRANSFORMER MOVABLY LOCATED IN SAID HOUSING HAVING TWO SETS OFTERMINALS, (C) A LAMP BULB CONNECTED TO A FIRST OF SAID TERMINAL SETS,(D) GUIDE MEANS IN SAID HOUSING TO GUIDE SAID TRANSFORMER MOVEMENT, (E)A LENS AT LEAST PARTIALLY ENCLOSING SAID LAMP BULB AND MECHANICALLYCONNECTED TO SAID TRANSFORMER FOR MOVEMENT THEREWITH, (F) SWITCH MEANSACTUATED BY MOVEMENT OF SAID TRANSFORMER,